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and distribution of chargers are very crucial to be able to accommodate those parameters appropriately. PHEV and BEV basically share the same charging standards; therefore, there is no peculiar charger features or requirements for each vehicle. Charger is designed to be able to communicate with the vehicle to ensure the safety and appropriate electricity flow. In addition, charger also monitors the earth leakage at the surrounding ground. On the other hand, battery management system (BMS) is installed in the vehicle as a very vital component, which is performing a thermal management, cell balancing and monitoring of over-charge and discharge of the battery pack. The battery pack consists of many individual cells having certain safe low working voltage. Therefore, it is very crucial to ensure that they are operating within the permitted range to avoid shorter battery life and battery failures, including fire. Chargers can be installed on-board and off-board. The on-board charger limits its electricity flow because of some constraints, such as weight and space. It can be performed though con- ductive (direct contact through charging connector and cable) and inductive ways (using the electromagnetic field). On the other hand, the off-board charger is installed externally; there- fore, there is no limitation related to size and weight. The electricity flow from the charger to vehicle is a DC flow; hence, high charging rate can be achieved. The direction of electricity between charger and vehicle can be classified into unidirectional and bidirectional flows. The former only facilitates a single direction charging from external charger to the vehicle (battery). The latter provides the possibility of charging and discharg- ing the electricity to and from the vehicle. Through bidirectional charging the utilization of PHEVs and BEVs is greatly widen. Correlated to the charging rate, chargers or electric vehicle supply equipment (EVSEs) can be classified by its maximum amount of electricity possibly charged to the battery of PHEV or BEV, as follows: a. Level-1 charging Level-1 charging utilizes the on-board charger and is compatible with the household elec- trical socket and power, which generally has voltage of 100 or 200 V (AC) depending on the region. This level of charging can facilitate charging rate up to about 4 kW. This level of charging is suitable for the overnight charging at the ordinary household without the need of additional device installation. b. Level-2 charging This level of charging has the purpose of improving the charging rate by using the dedi- cated mounted-box. This level-2 charging can supply power of 4−20 kW, with a maximum voltage of 400 V (AC three phase), depending on the available capacity of local supply. Generally, this kind of chargers is installed at dedicated charging facilities including resi- dential areas or public spaces. The charging connectors for both level-1 and level-2 char- gers vary across the countries and manufactures. Hybrid Electric Vehicles66